body {
  background-color: #808080;
}

form {
  width: 400px;
  padding: 40px 10px;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background-color: #000000;
  text-align: center;
}

form h1,
form p {
  color: rgb(255, 255, 255);
  font-weight: 500;
}

form p {
  font-size: 10px;
}

form input[type="text"],
form input[type="password"] {
  border: 0;
  background: #000000; /* 背景色を黒に */
  color: #ffffff; /* 文字色を白に */
  display: block;
  margin: 20px auto;
  border: 2px solid #ff69b4;
  padding: 15px 10px;
  width: 200px;
  outline: none;
  border-radius: 24px;
  transition: 0.25s;
  text-align: center;
}

form input[type="text"]:focus,
form input[type="password"]:focus {
  width: 280px;
  background-color: #000000; /* フォーカス時も背景を黒に */
  color: #ffffff; /* フォーカス時も文字色を白に */
}

form input[type="submit"] {
  border: 0;
  background: none;
  display: block;
  margin: 20px auto;
  border: 2px solid #f0f8ff;
  padding: 15px 10px;
  width: 200px;
  outline: none;
  color: white;
  border-radius: 25px;
  transition: 0.25s;
  text-align: center;
  cursor: pointer;
}

form input[type="submit"]:hover {
  background-color: #ff69b4;
  border: 2px solid #ff69b4;
}

.register-link {
  margin-top: 20px;
  font-size: 14px;
  color: #ffffff;
  text-align: center;
}

.register-link a {
  color: #ff69b4;
  text-decoration: none;
  font-weight: bold;
}

.register-link a:hover {
  text-decoration: underline;
}